The present invention relates generally to optical fiber interconnection closures and, more particularly, to internal structures of optical fiber interconnection closures.
Fiber optic networks typically include interconnection closures at various splice locations throughout the fiber optic network. Typically, these interconnection closures include splice closures and patch closures. For example, splice closures commonly house the splices connecting the optical fibers of one or more distribution cables to respective ones of the optical fibers of a fiber optic feeder cable. By housing the splices, a splice closure protects the spliced end portions of the optical fibers from environmental degradation, strain, and other deleterious forces, thereby increasing the reliability and quality of the splices.
As known to those of ordinary skill in the art, a variety of splice closures have been designed. For example, a typical butt-type splice closure includes a housing open at one end and a single end cap positioned within the open end of the housing. Each of the fiber optic cables associated with the butt-type splice closure extends through the single end cap. As an additional example, a typical in-line splice closure includes a housing open at both of its opposite ends and a pair of end caps respectively positioned within the open ends of the housing so fiber optic cables can enter the in-line splice closure from either end of the housing.
Conventional splice closures of the above-described types generally include a frame that is connected to the end cap(s) and carries a number of splice trays that are disposed in a stacked arrangement within the housing. Each splice tray generally includes a series of splice holders for receiving the spliced end portions of a pair of optical fibers.
As optical fibers continue to be used in greater numbers, the demand increases for splice closures that can carry and provide access to large numbers of fiber optic cables, optical fibers, and optical fiber splices. Whereas some conventional splice closures can be characterized as sufficiently carrying and providing access to large numbers of fiber optic cables, optical fibers, and optical fiber splices, there is always a demand for new splice closure structures that enhance the capability for optimally carrying and providing access to large numbers of fiber optic cables, optical fibers, and optical fiber splices.
The present invention provides splice closures and components of splice closures that enhance the capability for optimally carrying and providing access to large numbers of fiber optic cables, optical fibers, and optical fiber splices.
In accordance with one aspect of the present invention, a closure for receiving at least one fiber optic cable and for containing optical fibers and optical fiber splices is provided. The closure includes an elongate housing having front and rear ends. The housing extends in a longitudinal direction extending between the front and rear ends. The housing defines an internal cavity extending in the longitudinal direction, and at least one opening to the internal cavity. An end cap occludes the opening of the housing. The end cap defines ports through which fiber optic cables extend. The end cap includes a periphery extending around the ports. A support frame is connected to the end cap, extends in the longitudinal direction, and is positioned in the internal cavity of the housing. The support frame includes an elongate support member having opposite front and rear ends. The support member extends in the longitudinal direction, the front end of the support member is oriented toward the front end of the housing, and the rear end of the support member is oriented toward the rear end of the housing. The support frame further includes upper and lower front extensions. Each of the front extensions is connected to the support member proximate to the front end of the support member. The front extensions extend away from the support member and diverge with respect to one another. The upper front extension is connected to the end cap at an upper position proximate to the periphery of the end cap. The lower front extension is connected to the end cap at a lower position proximate to the periphery of the end cap and distant from the upper position. A plurality of container-like devices for containing optical fibers are carried by the support member. At least two of the container-like devices are positioned on opposite sides of the support member from one another. Therefore, one of the two container-like devices can be accessed without accessing the other of the two container-like devices.
In accordance with one example of the present invention, each of the two container-like devices carried on opposite sides of the support member are slack baskets for containing at least some of the optical fibers. In accordance with another example of the present invention, one of the two container-like devices carried on opposite sides of the support member is a splice tray, and the other of the two container-like devices is a slack basket. In accordance with another example of the present invention, each of the two container-like devices carried on opposite sides of the support member are splice trays. In accordance with yet another example of the present invention, one of the two container-like devices carried on opposite sides of the support member is a slack basket, and the other of the two container-like devices is an organizer assembly. The organizer assembly includes a plurality of spaced apart partitions defining a plurality of receptacles for respectively receiving splice trays.
In accordance with another aspect of the present invention, an elongate channel and an elongate opening to the channel extend along the back side of an organizer assembly carried by the support member. A bottom side of the organizer assembly is oriented toward the support member, and the back side is adjacent to the bottom side and opposite from the tray-receiving openings to the receptacles of the organizer assembly. The channel is designed to receive and at least partially enclose a section of optical fibers extending between a first position proximate the end cap and a second position proximate the rear end of the organizer assembly. Therefore, the channel advantageously facilitates the routing of optical fibers within the closure.
In accordance with another aspect of the present invention, a transition plate is mounted to the top of an organizer assembly carried by the support member. The transition plate includes a surface and a plurality of protrusions protruding angularly away from the surface. Each protrusion defines an aperture for receiving a tie that holds at least some of the optical fibers. For example, at least one of the protrusions can be an arch, a tab, or the like. The transition plate advantageously facilitates the routing of optical fibers within the closure.
In accordance with another aspect of the present invention, an adjustment bracket is mounted in movable relation to the support member. The adjustment bracket is movable toward and away from an organizer assembly carried by the support member. The adjustment bracket is operative to abut the splice trays received by the receptacles of the organizer. The adjustment bracket at least partially secures splice trays within the closure. Further, the adjustment bracket can accommodate splice trays of different sizes.
In accordance with another aspect of the present invention, the front extensions of the support frame cooperate to define a generally U-like shape. More specifically, the support member portion of the support frame defines a member axis extending between the front and rear ends of the support member. Each of the front extensions extend both generally radially away from proximate the member axis and longitudinally away from proximate the front end of the support member.
In accordance with another aspect of the present invention, one or multiple flanges protrude from the front extensions. Strain relief brackets are mounted to respective flanges and receive fiber optic cables. The flanges are arranged so the strain relief brackets are optimally placed proximate the cable-receiving ports of the end cap.
In accordance with another aspect of the present invention, the support frame further includes upper and lower rear extensions. Each of the rear extensions is connected to the support frame proximate to the rear end of the support member. The rear extensions extend away from rear end of the support member, the rear extensions diverge with respect to one another, and the rear extensions extend toward the front end of the support member. Buffer tubes abut the rear extensions, and the rear extensions function to at least partially restrict movement of the buffer tubes, so the buffer tubes are maintained in an organized arrangement.
In accordance with another aspect of the present invention, two bars are joined together to provide the support frame and the support member can be characterized as a composite support member. The front ends of the bars are the front extensions of the support frame. More specifically, the front ends of the bars diverge from one another, in the longitudinal direction, and forwardly away from the front end of composite support member. The rear ends of the bars are the rear extensions of the support frame. More specifically, the rear ends of the bars diverge from one another and forwardly away from the rear end of the composite support member.
Whereas numerous butt-type closures are within the scope of the present invention, numerous in-line type closures are also within the scope of the present invention. For example, in accordance with one aspect of the present invention, the above-described rear extensions can be characterized as a first pair of rear extensions, and a second pair of rear extensions are connected to the first pair of rear extensions and extend rearward from the first pair of rear extensions. Further, a secondary end cap is connected to the second pair of rear extensions.
Accordingly, the present invention advantageously provides splice closures and components of splice closures that enhance the capability for optimally carrying and providing access to large numbers of fiber optic cables, optical fibers, and optical fiber splices.